Commercial Essential Oils Research Articles

The Inhibition of Non-albicans Candida Species and Uncommon Yeast Pathogens by Selected Essential Oils and Their Major Compounds.

The epidemiology of yeast infections and resistance to available antifungal drugs are rapidly increasing, and non-albicans Candida species and rare yeast species are increasingly emerging as major opportunistic pathogens. In order to identify new strategies to counter the threat of antimicrobial resistant microorganisms, essential oils (EOs) have become an important potential in the treatment of fungal infections. EOs and their bioactive pure compounds have been found to exhibit a wide range of remarkable biological activities. We investigated the in vitro antifungal activity of nine commercial EOs such as Thymus vulgaris (thyme red), Origanum vulgare (oregano), Lavandula vera (lavender), Pinus sylvestris (pine), Foeniculum vulgare (fennel), Melissa officinalis (lemon balm), Salvia officinalis (sage), Eugenia caryophyllata (clove) and Pelargonium asperum (geranium), and some of their main components (α-pinene, carvacrol, citronellal, eugenol, γ-terpinene, linalool, linalylacetate, terpinen-4-ol, thymol) against non-albicans Candida strains and uncommon yeasts. The EOs were analyzed by GC-MS, and their antifungal properties were evaluated by minimum inhibitory concentration and minimum fungicidal concentration parameters, in accordance with CLSI guidelines, with some modifications for EOs. Pine exhibited strong antifungal activity against the selected non-albicans Candida isolates and uncommon yeasts. In addition, lemon balm EOs and α-pinene exhibited strong antifungal activity against the selected non-albicans Candida yeasts. Thymol inhibited the growth of all uncommon yeasts. These data showed a promising potential application of EOs as natural adjuvant for management of infections by emerging non-albicans Candida species and uncommon pathogenic yeasts.

Antimicrobial activity of Commercial essential oils on human pathogens

Essential oils (EOs) are natural extracts from the seeds, stems, roots, flowers, bark and other parts of the plant prepared by steam distillation. They are complex, volatile, natural compounds formed by aromatic plants as secondary metabolites. They are known for their bactericidal, virucidal, fungicidal, sedative, anti-inflammatory, analgesic, spasmolytic and locally anesthetic properties. They are generally composed of a combination of substances like terpenes, phenolics, aldehydes or alcohols. The complex composition and different mechanisms of action of EOs may be an advantage over other antimicrobials to prevent the development of resistance of pathogenic bacteria. With this background, the aim of this study was to evaluate the antimicrobial activity of five essential oils like basil, lime, rosemary, thyme and canada balsam against 14 microbes. The effects of essential oil on the selected microbes were determined by agar well diffusion method. The zone of inhibition was observed and measured in millimeter. Essential oils which showed inhibitory diameter >15 mm were further tested to determine the minimum inhibitory concentration (MIC). S. aureus, E. coli, S. mutans, S. sanguinis, C. albicans and M. furfur were inhibited by all essential oils. K. pneumoniae, P. aeruginosa and E .faecalis were inhibited only by thyme and not by other essential oils. The MIC values ranged from 50% to 0.10%. The least MIC value of 0.10% was shown by thyme and basil to S. aureus, thyme to E.coli and all essential oils against C. albicans except lime.

Efficacy of 12 commercial essential oils as wheat protectants against stored-product beetles, and their acetylcholinesterase inhibitory activity

Efficacy of 12 commercial essential oils as wheat protectants against stored-product beetles, and their acetylcholinesterase inhibitory activity

Antimicrobial green silver nanoparticles in bone grafts functionalization for biomedical applications

In maxillofacial surgery and implantology clinical practice, infection processes are common during the healing and graft osseointegration. Microorganisms’ resistance to various antimicrobials has increased steadily through the widespread use of topical antibiotics, and new substances with antimicrobial properties are urgently necessary to avoid the infection processes in bone grafts. In the present study, bovine bone grafts (BG) for dental application were functionalized with silver nanoparticles (NPs) synthesized by the bioreduction technique using extracted (EEO) and commercial orange essential oil (CEO). The majoritarian compound identified in EEO and CEO was d-limonene, with a concentration up to 95%. The UV–Vis spectroscopy of NPs demonstrated the maximum absorbance peak around 400 nm and the average diameter obtained by transmission electron microscopy was 50 and 80 nm, respectively for NPs-EEO and NPs-CEO. The physicochemical stability of the NPs was studied for 60 days, at refrigerated temperature (6 ± 2 °C), and NPs-EEO presented better results of zeta potential, polydispersity index, and particle size during storage. The antioxidant activity was determined by the inhibition of DPPH and ABTS free radicals and by the Fe3+ reducing power (FRAP assay). NPs showed better results of antioxidant activity by DPPH and FRAP methods when compared to individualized essential oils. NPs and functionalized bone grafts showed greater antagonistic actions than individualized essential oils against the seven studied microorganisms. Therefore, it is possible to affirm the biological importance of the biosynthesized NPs for use as an antimicrobial agent in dental biomaterials, being a promising alternative to avoid the infection processes in bone grafts.

Novel Strategy for the Recognition of Adulterant Vegetable Oils in Essential Oils Commonly Used in Food Industries by Applying 13C NMR Spectroscopy.

Essential oils (EOs) are valuable products commonly employed in the food industry and intensively studied as biopreservatives for the extension of food shelf-life. Unfortunately, EOs might be counterfeit to increase industrial profits. Among the possible adulterants, vegetable oils (VOs) must be considered for their characteristics and low costs. We aimed to apply nuclear magnetic resonance (NMR) spectroscopy for the detection and identification of VOs in mixtures with EOs. This innovative strategy is based on comparing the peak area ratio matrices of characteristic VO 13C NMR fatty acid signals with those of adulterated EOs. The identification of the VOs was achieved by calculating the matrix similarity at different confidence levels. The strategy demonstrated the capacity to efficiently recognize the presence of adulteration and the type of VO adulterant in mixtures. Thus, the method was applied to 20 commercial EOs, and VOs were detected and then identified in four samples.

Green NP-HPTLC and green RP-HPTLC methods for the determination of thymoquinone: A contrast of validation parameters and greenness assessment.

Thymoquinone (TQ) is a naturally derived bioactive compound with several therapeutic effects. The highly sensitive, rapid and green normal-phase (NP)/reversed-phase (RP) high-performance thin-layer chromatography (HPTLC) densitometry technique was developed for the determination of TQ in various plant extracts of different geographical regions, commercial capsules, creams and essential oils. The NP densitometry estimation of TQ was performed using a cyclohexane-ethyl acetate (90:10, v/v) green solvent system, while, the RP-densitometry estimation of TQ was performed using an ethanol-water (80:20, v/v) green solvent system. The estimation of TQ was conducted at 259 nm. The NP and RP densitometry techniques were observed linear in the range of 25-1000 and 50-600 ng/band, respectively. All validation parameters such as accuracy, precision, robustness and sensitivity of NP/RP densitometry were observed within the limit of regulatory requirements and hence found to be suitable for the determination of TQ. The TQ contents were found to be highest in the Saudi Arabian extract followed by the Syrian extract, Indian extract, commercial capsules, commercial creams, Jordanian extract, Egyptian extract, Palestinian extract and commercial essential oils using NP densitometry. The TQ contents were found in same order using RP densitometry, but they were much lower than those recorded using NP densitometry. The Analytical GREEnness (AGREE) scores of NP and RP densitometry were found to be 0.82 and 0.84, respectively, suggesting an excellent greenness profile. Based on these results, NP/RP densitometry was found to be suitable for the pharmaceutical assay of TQ.

Phytomanagement of a metal(loid)-contaminated agricultural site using aromatic and medicinal plants to produce essential oils: analysis of the metal(loid) fate in the value chain.

Phytomanagement uses plants and soil conditioners to create value on contaminated land while minimizing environmental risk. This work was carried out on a metal(loid)-contaminated site and aimed at assessing the suitability of Salvia sclarea L. (sage) and Coriandrum sativum L. (coriander) combined with an arbuscular mycorrhizal fungus (AMF) inoculant to immobilize metal(loid)s and produce essential oils (EO). The effect of the inoculant on the transfer of metal(loid)s (ML, i.e., Cd, Cu, Pb, Zn, As, Ni, and Sb) to plants and the ML soil mobility were investigated. The ML concentrations in EO from both plant species and the valorization options for the distillation residues (soil conditioner, animal fodder, and anaerobic digestion) were studied. Sage was a suitable candidate for this value chain because it presents an excluder phenotype and the residues of oil extraction could be used as a soil conditioner. The metal concentrations in the sage EO were similar to those obtained from plants cultivated on an uncontaminated soil. These results indicate the suitability of sage harvested on the contaminated soil according to the ML fate in the whole value chain. Like the EO of sage, ML concentrations in the coriander EO did not differ from those in the commercial EO that were obtained from plants grown on uncontaminated soil. However, the use of distillation residues of coriander was limited by their relatively elevated Cd concentrations. The use of a mycorrhizal inoculum did not decrease the Cd mobility in soil for the coriander.

Antioxidant-rich Clove Extract, A Strong Antimicrobial Agent against Urinary Tract Infections-causing Bacteria in vitro.

Clove (Syzygium aromaticum) is an exotic culinary spice that has been used for centuries due to its known antimicrobial and antioxidant properties. The main aim of this study is to compare the antimicrobial activity and antioxidant capacity of clove ethanolic extract (CEE) and commercial clove essential oil (CEO) at a standardised eugenol content. Disk diffusion assay showed that CEE (2000 μg) was able to exhibit broad-spectrum inhibition against both Gram negative and Gram positive Urinary Tract Infections (UTIs)-causing pathogens: Proteus mirabilis (19.7 ± 0.6 mm) > Staphylococcus epidermidis (18 mm) > Staphylococcus aureus (14.7 ± 0.6 mm) > Escherichia coli (12.7 ± 0.6 mm) > Klebsiella pneumoniae (12.3 ± 0.6 mm) (according to the size of inhibition zone). Interestingly, the comparison between CEE and commercial CEO revealed that the former demonstrated stronger antimicrobial and antioxidative properties at similar eugenol concentration. The EC50 of DPPH (1,1-diphenyl-2-picrylhydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and reducing power assay for CEE were determined as 0.037 mg/mL, 0.68 mg/mL and 0.44 mg/mL, respectively. Besides eugenol, High Performance Liquid Chromatography (HPLC) analyses identified the presence of kaempferol, gallic acid and catechin in CEE. As a conclusion, we concluded that there was a possible synergistic effect between eugenol and the others active compounds especially kaempferol which led to the observed bioactivities in CEE.

Comparison of sensitivity to a commercial Origanum vulgare essential oil between extended-spectrum β-lactamases (ESBL-) and non-ESBL-producing Enterobacteriaceae isolates

This study aimed to evaluate the antibacterial effect of Origanum vulgare essential oil (OVEO) against ESBL- and non-ESBL-producing multidrug-resistant (MDR) Enterobacteriaceae isolates. OVEO composition was determined using Gas chromatograph-mass spectrometer (GC/MS). In the current study, the effect of OVEO was studied on seven MDR Enterobacteriaceae isolates. Antibacterial activity of OVEO was investigated by the disc diffusion assay and twofold serial dilution method. GC/MS analysis identified thymol (78.21%) as the single major component present in the OVEO. This EO showed an unexpectedly high antibacterial activity against all the studied MDR Enterobacteriaceae isolates, with inhibition zone diameters and minimum inhibitory concentration (MIC) values ranging from 28 ± 0.6 to 35 ± 0.6 mm and 0.31 ± 0.0 to 5 ± 0.0 μL/mL, respectively. However, ESBL-producing isolates were more susceptible to OVEO than non-ESBL producing isolates. This study compared, for the first time, the sensitivity to OVEO between ESBL and non-ESBL-producing Enterobacteriaceae isolates.

Antibacterial Activities of Homemade Matrices Miming Essential Oils Compared to Commercial Ones.

The increasing bacterial resistance to antibiotics is a worldwide concern. Essential oils are known to possess remarkable antibacterial properties, but their high chemical variability complicates their development into new antibacterial agents. Therefore, the main purpose of this study was to standardize their chemical composition. Several commercial essential oils of ajowan (Trachyspermum ammi L.) and thyme (chemotype thymol) (Thymus vulgaris L.) were bought on the market. GC–MS analysis revealed that thyme essential oils have a chemical composition far more consistent than ajowan essential oils. Sometimes thymol was not even the major compound. The most abundant compounds and the homemade mixtures were tested against two Staphylococcus aureus strains. The antibacterial property of β-caryophyllene presented no direct activity against S. aureus LMG 15975, but in association with thymol or carvacrol at equal percentages an MIC of 125 μg/mL was observed. The mixture of those three compounds at equivalent percentages also decreased by 16-fold the MIC of the penicillin V. Against S. aureus LMG 21674, β-caryophyllene presented an MIC of 31.3 μg/mL and decreased by 267-fold the MIC of the penicillin V. These observations led us to question the benefits of using a complex chemical mixture instead of one active compound to fight bacterial resistance.

Fabrication of genetically encoded fluorescent sensor cells for the detection of cortisol

Live cell-based biosensors have emerged as a useful tool for biotechnology and chemical biology. In fabrication of genetically encoded fluorescent sensor cells, we previously reported intein based biosensor for detection of signaling molecules in live cells. While useful, previous system required long response time because the CAAX tag need to be prenylated to deliver fluorescent cargo to the plasma membrane. Here, we designed faster genetically encoded sensor cells that can report the presence of biologically active molecules via fluorescence-translocation based on split intein-mediated reactions. We utilized both conditional protein trans-splicing (PTS) triggered by signaling molecules, to activate the fluorophore-conjugated signal peptides. This approach fully valued the bond-making features of intein-mediated reactions in the design and thus eliminated the false-positive signals resulting from the mere binding of fragmented reporters and also possessed higher sensitivity. We could also avoid the necessity of designing split reporters to refold into active structures upon reconstitution. These live cell-based sensors were able to detect biologically active signaling molecules, cortisol, as well as relevant biological stimuli present in commercial essential oils. These live cell-based biosensors can be applied to drug screening and toxicology studies, which require functional information about targets.

Acaricidal activity and repellency of commercial essential oils on Tetranychus urticae in vitro and protected cultivation

This study analyzed the toxicity by residual contact and the repellency effect of the essential oils of Rosmarinus officinalis, Mentha piperita, Melaleuca alternifolia, and Commiphora myrrha and their mixtures on adult females of Tetranychus urticae in laboratory and protected cultivation. The essential oil of C. myrrha exhibited a LC50 of 0.55 ml L-1, and the mixtures R. officinalis + M. piperita + M. alternifolia + C. myrrha, C. myrrha + M. piperita, and C. myrrha + M. alternifolia showed 68%, 60%, and 36% mortality, respectively. The essential oils of C. myrrha and M. alternifolia showed 95 and 70% of repellency, respectively. Mixtures of C. myrrha + M. alternifolia, C. myrrha + M. piperita, and C. myrrha + R. officinalis provided repellency of 85, 74 and 73%, respectively. Toxicity by residual contact of the essential oil of C. myrrha in protected cultivation exhibited 93% mortality, while the acaricide fenpyroximate showed 80%. The constituents of essential oils were eucalyptol (49.66%), M. piperita menthol (48.53%), M. alternifolia terpinen-4-ol (48.93%), and C. myrrha benzyl benzoate (97.71%). The essential oil of C. myrrha and the mixtures R. officinalis + M. piperita + M. alternifolia + C. myrrha and C. myrrha + M. piperita showed significant mortality. However, further studies are needed to assess the cost/benefit ratio and the effects on non-target organisms.

Comparison between thin-layer chromatography and overpressured layer chromatography fingerprints of commercial essential oils and accelerated solvent extraction plant extracts

Comparison between thin-layer chromatography and overpressured layer chromatography fingerprints of commercial essential oils and accelerated solvent extraction plant extracts

Similarity analysis of essential oils and oleoresins of Eucalyptus globulus leaves produced by distinct methods, solvents and operating conditions

Eucalyptus globulus leaves can be a source of differentiated essential oil and extracted oleoresin products based on the wise choice of extraction methods, solvents and operating conditions. Accordingly, we performed 36 experimental assays combining extraction techniques (Soxhlet, batch solid-liquid extraction — SLE, supercritical fluid extraction, and hydrodistillation), solvents (supercritical CO2, water, dichloromethane, ethanol, methanol, n-hexane, petroleum ether, ethyl acetate and isopropanol) and operating conditions (temperature and particle size). The resulting products were analysed and compared (including with two commercial essential oils) in terms of total extraction yield, ηTotal, and chemical composition (by FTIR-ATR). Concerning ηTotal, the results ranged from 0.79 wt.% (n-hexane SLE at 20 °C) to 37.80 wt.% (Soxhlet with methanol). By applying multidimensional scaling (MDS) for the similarity analysis, Soxhlet and batch SLE products were grouped together, but the temperature of extraction strongly influences the composition of products from polar solvents. In turn, the spectra of both commercial and hydrodistillated oils exhibited a great similarity to pure eucalyptol. Finally, supercritical products differed on the composition in relation to all the other samples, evidencing an opportunity for a new niche type of product.

Tunisian essential oils as potential food antimicrobials and antioxidants and screening of their element profile

The potential employment of 18 commercial Tunisian essential oils (EOs) as natural food preservatives was investigated. Their antimicrobial activity was evaluated against two food-borne bacteria (Escherichia coli O157:H7 and Klebsiella pneumoniae) by the agar-well diffusion method and, subsequently, by determining the minimum inhibitory concentration (MIC); while their antioxidant activity was assayed by the DPPH test. Also, the main volatile constituents and inorganic elements were elucidated and discussed in relation to the biological activities. Excluding the wormwood EO, all EOs inhibited the growth of at least one reference strain. In particular, spearmint, sage and rosemary EOs had the lowest MICs against E. coli O157:H7 (0.09, 0.09, 0.07 mg mL−1, respectively); whereas sage EO was effective against K. pneumoniae at 0.41 mg mL−1. All EOs displayed also a promising antioxidant activity. Specifically, spearmint, bigroot geranium, and sage EOs showed the lowest IC50 values (0.024, 0.046 and 0.052 mg mL−1), and a behavior similar to that of butylated hydroxytoluene. EOs exhibited variegated and peculiar element profiles. Among minerals, Mg and K were in the range 1.72–14.12 mg Kg−1 and 0.57–20.90 mg Kg−1; while Cu and Fe were generally the most abundant trace essential metals (0.07–1.02 mg Kg−1 0.20–2.98 mg Kg−1, respectively). Very low and safe levels of heavy metals were also revealed. A statistical correlation analysis pointed out a significant positive correlation between some elements (K, Cu, and Fe) and the biological activities displayed. In conclusion, the selected Tunisian EOs had a marked potential applicability as antibacterial and antioxidant additive in food industry.

Natural Agents against Bovine Mastitis Pathogens.

Bovine mastitis is the most widespread and economically important disease worldwide. The present study aimed to determine bioactive compounds in two essential oils (EOs) from wild (Thymus serpyllum) and common thyme (Thymus vulgaris) and to assess the antioxidant potential as well as antibacterial efficacy of the EOs against mastitis-associated bacteria. The study also included antibiotic susceptibility tests. The strains were previously isolated from lactating animals with clinical and subclinical mastitis. The antioxidant potential of the commercial EOs of wild and common thyme was evaluated by five in vitro assays. The antibacterial activity was performed using the microdilution technique, while antibiotic susceptibility testing was performed by the Kirby–Bauer disc diffusion method. The dominant compound in wild thyme was thymol (45.22%), followed by p-cymene (23.83%) and γ-terpinene (3.12%), while in common thyme, it was thymol (54.17%), followed by γ-terpinene (22.18%) and p-cymene (16.66%). Among the fourteen mastitis-associated bacteria, strain IX Streptococcus spp. (β-hemolytic) was the most sensitive to the tested EOs (minimum inhibitory concentration (MIC)/minimal bactericidal concentration (MBC) were 0.78/1.56 and 0.39/0.78 mg/mL for T. serpyllum (TS) and T. vulgaris (TV), respectively). Regarding Streptococcus spp. β heamoliticus, MICs for TS ranged from 0.78 to 1.56 mg/mL, while for the same oil, MBCs ranged from 1.56 to 12.5 mg/mL. In the case of T. vulgaris, MICs ranged from 0.39 to 3.125 mg/ mL, while MBCs ranged from 3.125 to 6.25 mg/mL. TV is more active against E. coli, E. sakazakii, and Streptococcus spp., while it is less effective against Staphylococcus spp. than TS. The study revealed that the tested EOs possess remarkable antioxidative and antibacterial activities and could be used in the development of pharmaceutical formulation as an alternative to conventional mastitis therapy.

Insecticidal efficacy of some essential oils against adults of Musca domestica L. (Diptera: Muscidae)

Nowadays, the insecticidal and acaricidal properties of plant extracts and essential oils (EOs) have been evaluated as an alternative to chemical means. This study aims to assess the insecticidal efficacy of 20 commercial EOs against the adults of Musca domestica Linnaeus (Diptera: Muscidae) by the contact of insects with the residues of EOs at the bottom of glass cups. The dose effects of seven EOs (i.e. Acorus calamus, Allium sativum, Syzygium aromaticum, Cymbopogon citratus, Juniperus communis, Cedrus atlantica, and Foeniculum vulgare) as well as the time effects of exposure to these EOs on the mortality of flies were analyzed by probit analysis. Permethrin (technical substance) was used as a reference insecticide in the positive control and pure acetone served as the negative control. The insecticidal efficacy of the tested EOs decreased in order (based on their lethal dose (LD)50 values): A. calamus > A. sativum > S. aromaticum ≥ C. citratus > J. communis > C. atlantica > F. vulgare. A. calamus EO was the most effective against flies and very fast acting with negligible reversibility of effect. The EOs of A. sativum and S. aromaticum had a significant time-dependent insecticidal effect. The time for 50% insecticidal effect (knockdown and mortality in total) of the A. sativum EO was the greatest among the seven EOs and seven times more in comparison with the positive control. Present results and literature data suggest that the aforesaid plant products could be promising as contact insecticides against adults M. domestica. The difference in the insecticidal properties of A. calamus and A. sativum EOs observed in the current study display the need for various approaches for their future application as insecticides.

Chemical composition and antifungal properties of commercial essential oils against the maize phytopathogenic fungus Fusarium verticillioides

The aim of the present study was to analyze the chemical composition of Curcuma longa, Pimenta dioica, Rosmarinus officinalis, and Syzygium aromaticum essential oils (EOs) and their antifungal and anti-conidiogenic activity against Fusarium verticillioides. The chemical profile of the EOs was determined by GC/MS. The antifungal and anti-conidiogenic activities were evaluated by the agar dilution method. The tested concentrations were 1000ppm, 500ppm, 250ppm and 125ppm. S. aromaticum EO exhibited the highest antifungal effect, followed by P. dioica and to a lesser extent C. longa. The major compounds of these EOs were eugenol (88.70% in S. aromaticum and 16.70% in P. dioica), methyl eugenol (53.09% in P. dioica), and α-turmerone (44.70%), β-turmerone (20.67%), and Ar-turmerone (17.27%) in C. longa. Rosmarinus officinalis poorly inhibited fungal growth; however, it was the only EO that inhibited conidial production, with its major components being 1,8-cineole (53.48%), α-pinene (15.65%), and (−)-camphor (9.57%). Our results showed that some compounds are capable of decreasing mycelial growth without affecting sporulation, and vice versa. However, not all the compounds of an EO are responsible for its bioactivity. In the present work, we were able to identify different major compounds or mixtures of major compounds that were responsible for antifungal and anti-conidiogenic effects. Further experiments combining these pure components are necessary in order to achieve a highly bioactive natural formulation against the phytopathogenic fungus F. verticillioides.

Essential oils and their components in combating fungal pathogens of animal and human skin

ObjectiveThe most common problems of modern medicine include fungal infections of the skin and its appendages caused by dermatomycetes, yeast-like fungi and moulds. Due to toxicity of pharmacological fungicides and promotion of ecology, natural substances with high antifungal properties are sought. Essential oils and their components show potential in this regard. Material and methodFourteen commercial essential oils were tested for antifungal activity. The study were carried out by agar dilution method against the following fungal species: Microsporum gypseum, Microsporum canis, Trichophyton mentagrophytes, Trichophyton violaceum, Aspergillus niger, Scopulariopsis brevicaulis and (IZ 1) dog skin isolate. The minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) values were determined for all tested oils and individual components of oils with the highest activity against the tested fungi. GC-MS analysis was performed for the most active oils. ResultsCinnamon, thyme, clove, geranium and manuka oils were most active against the test fungi. The MIC values in the tested oils were in the range of 0.5–>10μg/μl and the MFC amounted to 1.25–>10μg/μl. Activity of individual components against the tested fungi strains was selective and clearly higher against dermatomycetes fungi and IZ 1 isolate. The strongest effect on dermatomycetes fungi was of cinnamaldehyde, thymol and carvacrol–with the values of 0.039–1.25μg/μl (MIC) and 0.078–1.25μg/μl (MFC). In turn, the highest activity against IZ 1 isolate was of cinnamaldehyde, eugenol, carvacrol, geraniol and thymol. Their MIC and MFC was 0.313–1.25μg/μl. ConclusionThe results prove the applicability of selected oils and their components as alternatives to synthetic agents in combating fungal dermatoses in animals and humans.

Origanum vulgare L. essential oil effects on microbial pathogens causing vaginitis

Multidrug resistance of human isolates of bacteria that cause vaginal infections is one of most recent topics in scientific investigations along with the search for novel antimicrobial drugs originating from nature. Monitoring of antimicrobial activity of traditionally used herbal essential oils may give us basic perspective and directions for future studies design. Antimicrobial activity of commercial essential oil (EO) of Origanum vulgare against human clinical isolates of bacteria and Candida was determined by microdilution method, obtaining minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) (CLSI protocol). Both investigated strains of Candida as well as all bacterial strains, except P. aeruginosa, showed susceptibility to investigated EO. The most susceptible strain was Gram positive S. aureus1 strain unlike S. aureus2 which indicates strain specificity. Both Gram negative E. coli isolates (E. coli1 and E. coli2) showed resistance to all tested antibiotics in this study, and susceptibility to oregano EO at 12.5 ?l/ml. GC/MS analysis identified a total of 35 components (96.13%) in commercial oregano EO, with the most dominant phenol carvacrol (64.12%). Our data suggest that oregano EO possess potent antimicrobial activity and that human vaginal isolates shows strain specificity in antimicrobial susceptibility.